Sainfoin is a fast-spreading plant with attractive flowers—a good cover choice.

Each time we plant flowers and vegetables, we deplete the garden soil of vital nutrients and organic matter. Without replenishment, the soil loses its power to feed your plants. To feed your soil, consider cover crops, or fast-spreading plants grown for the sole purpose of improving your soil. Cover crops, also called green manures, prevent erosion, control weeds, are inexpensive, and are easy to grow.

There are several types of cover crops you can use in your garden or landscape. Cover crops are broken into two categories: legumes and non-legumes, which are mostly grasses. Popular legumes include hairy vetch, cowpeas, and clovers. Grasses and other non-legumes include annual rye grass, oats, buckwheat, and Brassica. Each cover crop can serve a different purpose, so do your research to find which one is best for you.

5. Nutrient retainers—A bare, off-season garden loses nutrients through leaching. The roots of cover crops act as holding tanks for these vital nutrients, keeping them in place until your flowers and vegetables can use them.

6. Soil retainers—Neither wind, nor rain, nor snow will take away your soil. Weather conditions disturb the soil and cause erosion. The foliage from cover crops works on the surface to keep the dirt in place.

7. Nutrient pumps—Just like oil rigs, the long-rooted varieties of cover crops draw nutrients from deep within the soil to ground level, where your flowers and vegetables can access them.

8. Nitrogen heaven—Legume varieties of cover crops are nitrogen lovers, sucking nitrogen from the air and storing it in nodules in the roots. Once tilled into the soil, the nitrogen is released and ready to feed your plants.